In certain types of windows, including casement and awning windows, it is desirable to incorporate a mechanism to limit the amount that the window sash can be opened. This is both for safety reasons and to limit, in certain circumstances, the ventilation flow through the window. It also is desirable to be able to bypass the mechanism when desired to allow the window sash to be opened fully. Recent ASTM standards (ASTM F2090-8 and -10 for example) require that such mechanisms incorporate a “dual action release” for bypassing the mechanism to allow the window sash to be opened beyond its limited amount. A dual action release requires two distinct motions to release the limiting mechanisms, which serves as a child safety feature since small children are less likely to be able to bypass the limiting mechanism. In some jurisdictions, windows that comply with these standards are allowed as code compliant child safety devices. In any case, features that inhibit full opening of the window sash by small children help to protect children from falling out of a window and thus can save precious lives.
At least one commercial casement/awning window offers an opening control mechanism that attempts to meet the ASTM standard mentioned above. However, the mechanism of this product is cumbersome to release when it is desired to open the window beyond its limited amount at least in part because the window screen, which resides on the inside of a casement or awning window, must be removed to access the release mechanism. The screen must be removed again to re-engage the opening control mechanism. In addition, the mechanism of this existing device mounts to the side jamb of the window, which can impede egress through the window in the event of an emergency.
A need exists for a window having an opening control mechanism, particularly for use with casement and awning windows, that effectively limits the amount that the window sash can be opened, that meets ASTM standards for child safety, that can be released and re-engaged without the need to remove an insect screen from the window, and that does not significantly impede egress through the window in an emergency. It is to the provision of such a window and such an opening control mechanism that the present disclosure id primarily directed.